Why did Islam make divorce easy with a single word, without witnesses or notification, while it made the procedures for the marriage contract strict?

Islam has made divorce a serious matter and imposed restrictions to reduce its occurrence. The default for divorce is prohibition unless there is a necessity. It was placed in the husband's hand to regulate it. It prohibited divorce during menstruation or during a period of purity in which intercourse occurred. It forbade expelling the wife from her home after divorce to allow an opportunity for reconciliation. It made the number of divorces three to provide room for reconsideration. It legislated admonition, boycotting, and non-injurious striking before resorting to it. It also commanded arbitration between the spouses. These rulings reduce the occurrence of divorce, which is detestable to Allah.